Delhi's Duplicate Image Problem: How the Capital Stacks Up Against Mumbai, London and Seoul

Delhi's three municipal corporations and the Delhi Development Authority collectively maintain tens of thousands of digitised photographs across heritage registers, property records, planning files and public-facing portals — and a significant share of those images are duplicates, mismatched or simply wrong. The problem has sharpened this year as the DDA pushes its land-use digitalisation drive ahead of the 2031 Master Plan revision cycle, with officials discovering that the same property in Shahdara or Rohini can appear under four different image tags in four separate databases.

The issue matters now because Delhi is simultaneously running the Smart Cities Mission legacy infrastructure audit and preparing digital documentation for the Delhi Metro Phase 4 corridor acquisitions along Janakpuri West and RK Ashram Marg. Duplicate or misattributed site photographs in land records have already complicated compensation hearings in at least some Phase 4 acquisition cases, according to publicly filed objections submitted to the Revenue Department earlier this year. When a photograph of one plot is filed against the record of an adjacent one, the downstream legal and financial consequences compound quickly.

A City Split Three Ways

The structural difficulty is straightforward: Delhi does not have a single civic body. The North, South and East Delhi Municipal Corporations — merged in 2022 into the unified Municipal Corporation of Delhi — inherited three separate IT systems, each with its own image-cataloguing logic. The DDA operates a fourth. The Delhi Urban Shelter Improvement Board runs a fifth. None of them uses a shared deduplication protocol. By contrast, the Brihanmumbai Municipal Corporation in Mumbai completed a centralised GIS photo repository rollout in 2024 that uses hash-based deduplication across its property tax and planning arms, a project funded partly through a World Bank urban resilience grant.

Seoul's approach is more instructive still. The Seoul Metropolitan Government embedded automated reverse-image matching inside its Eul-jiro Urban Regeneration portal as early as 2021, flagging duplicate building photographs before they enter the permanent record. The system, built on open-source tooling, cost roughly ₩3.2 billion (approximately Rs 20 crore at current rates) to deploy city-wide. Delhi's total IT modernisation budget under the 2025-26 MCD capital expenditure plan was not independently verifiable at time of publication, but the absence of any equivalent deduplication tender in the Central Public Procurement Portal as of July 2026 suggests the city has not yet committed dedicated funds to the problem.

London's approach differs from both. The Greater London Authority mandates that borough councils upload photographs to a shared cloud repository managed through the London DataStore, where duplicate detection runs automatically on ingest. The system does not eliminate all misattributed images — a 2024 audit of Southwark Council's planning portal found roughly 6 percent of site photographs tagged to incorrect addresses — but the single-ingest model at least prevents the same image propagating across multiple incompatible archives.

What Chandni Chowk and Dwarka Reveal

The practical stakes show up most visibly in Old Delhi. Heritage documentation for the Chandni Chowk Redevelopment Project, overseen by the Delhi Tourism and Transportation Development Corporation, runs to thousands of photographs of havelis, street elevations and utility corridors. Conservationists who have reviewed the public-facing archive note that images from different survey years appear in the same dated folder, making it difficult to establish a baseline condition for structures under restoration. The problem is less acute in newer neighbourhoods like Dwarka, where the DDA's sector-by-sector documentation was more standardised from the outset, but even there, photographs submitted by private builders during occupation certificate applications sometimes duplicate images already in the sanctioned plan file.

The MCD's Information Technology Department has been in discussions with National Informatics Centre about deploying a deduplication layer across the unified property records system. NIC has existing tooling from its land records modernisation work in other states that could, in principle, be adapted. Whether a formal procurement moves before the 2027 municipal budget cycle is the question civic technology advocates are now pressing.

For residents and professionals dealing with property transactions in areas like Lajpat Nagar, Patparganj or Narela right now, the practical advice from legal practitioners is consistent: independently photograph and timestamp every site visit, and never rely solely on the digital image attached to an official record as proof of current condition. The archive, for the moment, cannot vouch for itself.